EP4035996A1 - Aircraft propulsion system and methods of feathering - Google Patents

Aircraft propulsion system and methods of feathering Download PDF

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Publication number
EP4035996A1
EP4035996A1 EP22158348.7A EP22158348A EP4035996A1 EP 4035996 A1 EP4035996 A1 EP 4035996A1 EP 22158348 A EP22158348 A EP 22158348A EP 4035996 A1 EP4035996 A1 EP 4035996A1
Authority
EP
European Patent Office
Prior art keywords
aircraft
electric motor
propulsion system
air mover
heat engine
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
EP22158348.7A
Other languages
German (de)
French (fr)
Inventor
Jean Thomassin
Pierre Bertrand
Todd A. Spierling
Chad M. Henze
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Pratt and Whitney Canada Corp
Original Assignee
United Technologies Advanced Projects Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by United Technologies Advanced Projects Inc filed Critical United Technologies Advanced Projects Inc
Publication of EP4035996A1 publication Critical patent/EP4035996A1/en
Pending legal-status Critical Current

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64DEQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENTS OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
    • B64D35/00Transmitting power from power plant to propellers or rotors; Arrangements of transmissions
    • B64D35/08Transmitting power from power plant to propellers or rotors; Arrangements of transmissions characterised by the transmission being driven by a plurality of power plants
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64CAEROPLANES; HELICOPTERS
    • B64C11/00Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
    • B64C11/002Braking propellers, e.g. for measuring the power output of an engine
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64CAEROPLANES; HELICOPTERS
    • B64C11/00Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
    • B64C11/30Blade pitch-changing mechanisms
    • B64C11/32Blade pitch-changing mechanisms mechanical
    • B64C11/325Blade pitch-changing mechanisms mechanical comprising feathering, braking or stopping systems
    • B64D27/026
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64DEQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENTS OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
    • B64D27/00Arrangement or mounting of power plant in aircraft; Aircraft characterised thereby
    • B64D27/02Aircraft characterised by the type or position of power plant
    • B64D27/24Aircraft characterised by the type or position of power plant using steam, electricity, or spring force
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02TCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T50/00Aeronautics or air transport
    • Y02T50/60Efficient propulsion technologies, e.g. for aircraft

Abstract

An aircraft propulsion system including at least first air mover (216), an electric motor (220) configured to at least partially power the at least first air mover (216), wherein the first air mover (216) includes a propeller having at least a first position configured to provide thrust to the aircraft and a second position configured to recharge a power source, wherein the second position is a reverse windmilling position, and a heat engine (228) configured to at least partially power the first air mover (216) or a second air mover (217).

Description

    BACKGROUND OF THE INVENTION Field of the Invention
  • The subject invention is directed to an aircraft propulsion system having and more particularly, to a commercial passenger aircraft having a propulsion system that includes hybrid-electric powerplants.
  • Description of Related Art
  • The level of air traffic continues to increase worldwide, leading to increased fuel consumption and air pollution. Consequently, efforts are underway to make aircraft more environmentally compatible through the use of specific types of fuel and/or by reducing fuel consumption through the use of more efficient drive systems.
  • For example, aircraft having mixed drive systems that include a combination of various types of engines are known for reducing pollutants and increasing efficiency. Some current combinations include reciprocating engines and jet engines, reciprocating engines and rocket engines, jet engines and rocket engines, or turbojet engines and ramjet engines.
  • While these mixed drive systems are useful, they are not readily adaptable for use on commercial passenger aircraft. However, hybrid-electric propulsion systems that provide power through a combustion engine and an electric motor are indeed adaptable for use with commercial passenger aircraft and can provide efficiency benefits including reduced fuel consumption. The subject invention is directed to an aircraft having such a propulsion system.
  • SUMMARY OF THE DISCLOSURE
  • The subject disclosure is directed to a new and useful aircraft, aircraft propulsion system, and method of use of the system having a hybrid-electric powerplant, and a mode of recharging the system.
  • According to an aspect of the invention, an aircraft and aircraft propulsion system includes at least a first airmover, an electric motor configured to at least partially power the at least first airmover, wherein the first airmover includes a propeller having at least a first position configured to provide thrust to the aircraft and a second position configured to recharge a power source connected to the electric motor, wherein the second position is a reverse windmilling position of the airmover, and a heat engine configured to at least partially power the first air mover or a second air mover. The reverse windmilling position may include rotating at least one blade of the first air mover by at least 90 degrees compared with the first position.
  • In an embodiment of the above, the heat engine and the electric motor ia arranged in an in-line drive configuration.
  • In a further embodiment of any of the above, the heat engine and the electric motor are configured to drive a single combined gearbox.
  • In a further embodiment of any of the above, the heat engine and the electric motor are configured to drive separate airmovers.
  • In a further embodiment of any of the above, the heat engine and the electric motor are configured to power the first air mover separately and in combination.
  • In a further embodiment of any of the above, the heat engine and the electric motor are configured to drive the airmover by a concentric shaft.
  • In a further embodiment of any of the above, the heat engine and the electric motor are connected to separate respective and dedicated gearboxes.
  • In a further embodiment of any of the above, the aircraft propulsion system also includes a second air mover, a third air mover, a fourth air mover, wherein at least one of the airmovers is powered exclusively by the electric motor and at least one airmovers is powered exclusively by the heat engine.
  • Other configurations including more props and more airmovers is also envisioned.
  • In a further embodiment of any of the above, each of the airmovers powered exclusively by an electric motor is positioned outboard (relative to an aircraft fuselage) of the airmovers powered by a heat engine.
  • In a further embodiment of any of the above, each of the airmovers powered exclusively by an electric motor is positioned inboard (relative to a fuselage of the aircraft) of the airmovers powered by a heat engine.
  • In a further embodiment of any of the above, at least one of the air movers is in a pusher configuration (i.e. located behind the respective motor or engine) and/or at least one of the air movers is in a tractor configuration (i.e. located in front of the respective motor or engine).
  • In a further embodiment of any of the above, the heat engine is configured to power a first dedicated propeller and the electric motor is configured to power a second dedicated propeller.
  • There is also provided an aircraft having the propulsion system of any of the above.
  • According to a further aspect, a method of operating the aircraft propulsion system is also disclosed. The method includes reverse windmilling an airmover connected to electric motor and recharging a power supply while reverse windmilling the airmover.
  • In an embodiment of the above, the method further includes providing thrust to the aircraft by the airmover connected to the electric motor.
  • In a further embodiment of any of the above, the method further includes switching from providing thrust to the aircraft to reverse windmilling of the airmover and vice versa.
  • In a further embodiment of any of the above, switching to windmilling includes rotating at least one blade of the airmover by at least 90 degrees with respect to an operating position (in which the air mover is configured to provide thrust to the aircraft).
  • These and other features of the aircraft propulsion system of the subject invention will become more readily apparent to those having ordinary skill in the art to which the subject invention appertains from the detailed description of the preferred embodiments taken in conjunction with the following brief description of the drawings.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • So that those having ordinary skill in the art will readily understand how to make and use the subject invention without undue experimentation, preferred embodiments thereof will be described in detail herein below with reference to the figures wherein:
    • Fig. 1 is a top plan view of a commercial passenger aircraft having a propulsion system configured in accordance with an embodiment of the subject invention, which includes a combustion powerplant and a hybrid-electric powerplant within the same air mover;
    • Fig. 2 is a front elevational view of the aircraft illustrated in Fig. 1;
    • Fig. 3 is a left side front elevational view of the aircraft illustrated in Fig. 1;
    • Fig. 4 is a top plan view of a commercial passenger aircraft having a propulsion system configured in accordance with an embodiment of the subject invention, which includes a combustion powerplant and a hybrid-electric powerplant each dedicated to individual air movers;
    • Fig. 5 is a front elevational view of the aircraft illustrated in Fig. 4;
    • Fig. 6 is a left side front elevational view of the aircraft illustrated in Fig. 4;
    • Fig. 7 is a top plan view of a commercial passenger aircraft having a propulsion system configured in accordance with an embodiment of the subject invention, which includes a combustion powerplant and a hybrid-electric powerplant arranged as a pusher and a tractor configuration;
    • Fig. 8 is a front elevational view of the aircraft illustrated in Fig. 7;
    • Fig. 9 is a left side front elevational view of the aircraft illustrated in Fig. 7;
    • Fig. 10 is a top plan view of a commercial passenger aircraft having a propulsion system configured in accordance with an embodiment of the subject invention, which includes a combustion powerplant and a hybrid-electric powerplant arranged in a coaxial configuration;
    • Fig. 11 is a front elevational view of the aircraft illustrated in Fig. 10;
    • Fig. 12 is a left side front elevational view of the aircraft illustrated in Fig. 10; and
    • Fig. 13 is a series of wind milling positions of the rotors of Figures 1-12.
    DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
  • Referring now to the drawings wherein like reference numeral identify similar structure or features of the subject invention, there is illustrated in Figs. 1 through 13 a commercial passenger aircraft 10 having a propulsion system that is configured in accordance with a preferred embodiment of the subject invention.
  • The aircraft 10 includes a fuselage 12 designed to carry passengers, a left wing 14 and a right wing 24. Each wing 14/24 includes an airmover 16. An electric motor 20 is configured to at least partially power the airmover 16. The airmover 16 includes a propeller 22 having at least a first position configured to provide thrust to the aircraft 10 and a second position configured to recharge a power source 26 connected to the electric motor 20. The second position is a reverse windmilling position. A heat engine 28 is included to at least partially power the airmover 16.
  • It is envisioned that the electric motor 20 would be designed to output up to 1 MW or more of shaft power to propeller 22, with an output shaft speed of 12,000 RPM, or at any speed for the best combination of power density, heat management and efficiency, however other system providing are also envisioned .
  • It is also envisioned that the power source 26 (a battery system) would provide energy to the electric motor 20. The battery system could be located within the fuselage 12 of the aircraft 10 and/or within the wings 14, 24 of the aircraft 10, or in any other optimum location for space availability and proximity of use.
  • It is further envisioned that the heat engine 28 could be a heat engine of any type, e.g., a gas turbine, spark ignited, diesel, rotary or reciprocating engine of any fuel type with a configuration of turbomachinery elements, selected from a group consisting of a turbocharger, turbo-supercharger, or supercharger and exhaust recovery turbo compounding, which is mechanically, electrically, hydraulically or pneumatically driven. An example of a rotary engine suitable for this application is disclosed in U.S. Patent No. 10,145,291 .
  • Further shown in Fig. 1, the heat engine 28 and the electric motor 20 can be arranged in an in-line drive configuration. The heat engine and the electric motor can be configured to drive a single combined gearbox 30.
  • As show in Figs. 4-6 the aircraft can also include a second air mover 217, a third 218 air mover, and a fourth air mover 219. At least one of the airmovers 216-219 can be powered exclusively by an electric motor 220 and at least one airmovers can be powered exclusively by the heat engine 228. Each of the airmovers 218/219 powered exclusively by an electric motor 220 can be positioned outboard of the airmovers 216/217 powered by a heat engine 228. Alternatively it is conceived that the airmovers powered exclusively by an electric motor can be positioned inboard of the airmovers powered by a heat engine.
  • As shown in Figs. 7-9 at least one of the air movers 316/318 can be a pusher and at least one of the air movers can be a tractors. The heat engine 328 can be configured to power a first dedicated propeller 318 and the electric motor 320 can be configured to power a second dedicated propeller 316. The configuration show shows the air movers 316/318 set up in line.
  • As shown in Fig. 10-12, each heat engine 428 can be configured to power a first dedicated propeller 418 of each wing and each electric motor 420 can be configured to power a second dedicated propeller 416 of each wing. The propellers 418/416 are in line and can share a common shaft. This configuration allows an aft air mover to straighten flow, improving the efficiency of the system
  • A method of operating the aircraft propulsion system is also disclosed. The method includes reverse windmilling an airmover connected to electric motor and recharging a power supply while reverse windmilling the airmover. The method can further include providing thrust to the aircraft by the airmover connected to the electric motor. The method can further include switching from providing thrust to the aircraft to reverse windmilling of the airmover and vice versa. Switching to windmilling can include rotating at least one blade 13a of the airmover by at least 90 degrees with respect to an operating position as shown in in Fig. 13.
  • Any of the propulsion systems can be the result of a modification to an existing aircraft propulsion system having dual combustion power plants or be assembled as an initial configuration. Thus, the disclosure is also directed to a method of retrofitting an aircraft having a propulsion system with dual combustion powerplants.
  • While the systems and methods of the subject invention has been described with reference to preferred embodiments, those skilled in the art will readily appreciate that changes and/or modifications may be made thereto without departing from the scope of the subject disclosure.

Claims (15)

  1. An aircraft propulsion system comprising:
    a first air mover (16; 216);
    an electric motor (20; 220; 320; 420) configured to at least partially power the first air mover (16; 216), wherein the first air mover (16; 216) includes a propeller having a first position configured to provide thrust to an aircraft and a second position configured to recharge a power source, wherein the second position is a reverse windmilling position; and
    a heat engine (28; 228; 328; 428) configured to at least partially power the first air mover (16; 216) or a second air mover (217).
  2. The aircraft propulsion system as recited in claim 1, wherein the heat engine (28..428) and the electric motor (20..420) are arranged in an in-line drive configuration.
  3. The aircraft propulsion system as recited in any preceding claim, wherein the heat engine (28..438) and the electric motor (20..420) are configured to drive a single combined gearbox (30).
  4. The aircraft propulsion system as recited in any preceding claim, wherein the heat engine (28..428) and the electric motor (20..420) are configured to drive separate air movers (16; 216, 217, 218, 219).
  5. The aircraft propulsion system as recited in any preceding claim, wherein the heat engine (28..428) and the electric motor (20..420) are configured to power the first air mover (16; 216) separately and in combination.
  6. The aircraft propulsion system as recited in any preceding claim, wherein the heat engine (28..428) and the electric motor (20..420) are configured to drive the first air mover (16; 216) by a concentric shaft.
  7. The aircraft propulsion system as recited in any preceding claim, wherein the heat engine (28..428) and the electric motor (20..420) are connected to separate respective and dedicated gearboxes.
  8. The aircraft propulsion system of any preceding claim, wherein the heat engine (328; 438) is configured to power a first dedicated propeller (318; 418) and the electric motor (320; 420) is configured to power a second dedicated propeller (316; 416).
  9. The aircraft propulsion system of any preceding claim further comprising:
    a second air mover (217);
    a third air mover (218); and
    a fourth air mover (219), wherein at least one of the air movers (218, 219) is powered exclusively by the electric motor (220) and at least one air mover (216, 217) is powered exclusively by the heat engine (228).
  10. The aircraft propulsion system of claim 9, wherein each of the air movers (218, 219) powered exclusively by an electric motor (220) is/are positioned:
    outboard of the air movers (216, 217) powered by a heat engine (228); or
    inboard of the air movers powered by a heat engine (218).
  11. The aircraft propulsion system of claim 9 or 10, wherein at least one of the air movers (216...219) is a pusher and at least one of the air movers (216...219) is a tractor.
  12. An aircraft having a propulsion system according to any preceding claim.
  13. A method of operating an aircraft propulsion system comprising:
    reverse windmilling an air mover (16; 216, 217, 218, 219; 316, 318; 416, 418) connected to an electric motor (20..420); and
    recharging a power supply while reverse windmilling the air mover (16..418), optionally wherein reverse windmilling includes rotating at least one blade of the air mover (16...418) by at least 90 degrees with respect to an operating position.
  14. The method of claim 13, further comprising the step of providing thrust to the aircraft (10) by the air mover (16...418) connected to the electric motor (20..420).
  15. The method of claim 13 or 14, further comprising:
    switching from providing thrust to the aircraft to reverse windmilling of the air mover (16...418); and/or
    switching from reverse windmilling to providing thrust to the aircraft (10) by the air mover (16...418).
EP22158348.7A 2019-12-03 2020-12-03 Aircraft propulsion system and methods of feathering Pending EP4035996A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201962942969P 2019-12-03 2019-12-03
EP20211638.0A EP3831720A1 (en) 2019-12-03 2020-12-03 Aircraft propulsion system and methods of feathering

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EP20211638.0A Division EP3831720A1 (en) 2019-12-03 2020-12-03 Aircraft propulsion system and methods of feathering

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EP4035996A1 true EP4035996A1 (en) 2022-08-03

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EP20211638.0A Pending EP3831720A1 (en) 2019-12-03 2020-12-03 Aircraft propulsion system and methods of feathering
EP22158348.7A Pending EP4035996A1 (en) 2019-12-03 2020-12-03 Aircraft propulsion system and methods of feathering
EP22158347.9A Pending EP4035995A1 (en) 2019-12-03 2020-12-03 Aircraft propulsion system and methods of feathering

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EP (3) EP3831720A1 (en)
CA (1) CA3101391A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR3134079A1 (en) 2022-03-29 2023-10-06 Airbus Helicopters Propeller plane

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US20080184906A1 (en) * 2007-02-07 2008-08-07 Kejha Joseph B Long range hybrid electric airplane
US20170320584A1 (en) * 2016-05-05 2017-11-09 Pratt & Whitney Canada Corp. Hybrid gas-electric turbine engine
EP3335995A1 (en) * 2016-12-13 2018-06-20 General Electric Company Hybrid-electric drive system
US10145291B1 (en) 2017-10-10 2018-12-04 Pratt & Whitney Canada Corp. Rotary engine and method of combusting fuel

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CA2996844A1 (en) * 2014-08-29 2016-06-16 Tzunum, Inc. Power train for a hybrid-electric aircraft
GB201508139D0 (en) * 2015-05-13 2015-06-24 Rolls Royce Plc Aircraft propulsion system
US20200017228A1 (en) * 2018-07-16 2020-01-16 Ampaire, Inc. Parallel Hybrid Aircraft
US11225881B2 (en) * 2018-11-08 2022-01-18 Rolls-Royce North American Technologies, Inc. Hybrid propulsion systems
US11203439B2 (en) * 2019-10-18 2021-12-21 The Boeing Company Rotary electric engines, aircraft including the same, and associated methods

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Publication number Priority date Publication date Assignee Title
US20080184906A1 (en) * 2007-02-07 2008-08-07 Kejha Joseph B Long range hybrid electric airplane
US20170320584A1 (en) * 2016-05-05 2017-11-09 Pratt & Whitney Canada Corp. Hybrid gas-electric turbine engine
EP3335995A1 (en) * 2016-12-13 2018-06-20 General Electric Company Hybrid-electric drive system
US10145291B1 (en) 2017-10-10 2018-12-04 Pratt & Whitney Canada Corp. Rotary engine and method of combusting fuel

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CA3101391A1 (en) 2021-06-03
EP4035995A1 (en) 2022-08-03
US20210300574A1 (en) 2021-09-30
EP3831720A1 (en) 2021-06-09

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